Sorry, but with "best", "easiest", and "durable" you can only pick 2 of the 3. If you limit this to "easiest" and "durable", you can pick 1.
On a serious note, you did not say that you are looking for something that is "factory like" or "concours".
For something like that, I have access to (did not have to buy
a $500 spray gun - something used in many body shops. The material in a caulk gun tube is about $20 a tube, and it takes 2 to 4 to do a car depending on how much was salvaged (not removed).
But to do a small spot or touch up, it is not fun to crack that $20 tube and use a small amount, followed up by cleaning the gun.
I have found that the spray can el-cheapo stuff is too runny. It tends to self level and looks nothing like the factory applied material.
Very interested in other experiences.